I am satisfied with 2 additional channels resulting in angles of mlutiples of 11.25° (this I have tested and it works - thanks to all contributors of this thread ), 4 additional channels will result in 2.8° angles (not tested by myself). Please let us know if it works, because 17 channels are one more as two bytes (16 channels), I wonder if this gdm can be converted into png.

I am satisfied with 2 additional channels resulting in angles of mlutiples of 11.25° (this I have tested and it works - thanks to all contributors of this thread ), 4 additional channels will result in 2.8° angles (not tested by myself). Please let us know if it works, because 17 channels are one more as two bytes (16 channels), I wonder if this gdm can be converted into png.

Greetings TracMax

Thank you for this. I actually got it working on a fresh start of the map I was working on, with numAdditionalAngleChannels = 3 and numDensityMapChannels: 16, combinedValuesChannels "0 3 0:6 5 0:3 3 1" and 31/32 in the groundshaderxml. Someone else on another site or maybe YouTube (can't remember) showed that, and I went with it, and am satisfied with it.

However thank you very much for the info provided as maybe in the future I will change to that.

@canons
I never got this error in combination with the multi terrain angle. So I suggest something else got wrong or you have a typewriter error either in modDesc.xml or ModMap.lua.
For comparison an extract of my modDesc.xml